Revert "[PE] Don't call PaintController::FinishCycle() if not repainted"

This reverts commit e71a3846.

Reason for revert: Caused performance regressions because changed
paint properties are not cleared changed flags.

Original change's description:
> [PE] Don't call PaintController::FinishCycle() if not repainted
> 
> This is mainly a performance optimization because we don't need
> FinishCycle() if PaintController has nothing changed.
> 
> By the way it can also avoid the immediate bad effect (but not the
> root cause) of bug 859294.
> 
> Bug: 859294
> Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_slimming_paint_v2;master.tryserver.blink:linux_trusty_blink_rel
> Change-Id: Iad3e14ee303c08185922d3d6e495c3b25ead5434
> Reviewed-on: https://chromium-review.googlesource.com/1121783
> Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
> Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#571803}

TBR=wangxianzhu@chromium.org,chrishtr@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 859294, 859885
Change-Id: I2a4d2a7d09cc3bf5edfbf0c6dee275581030c2c9
Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_slimming_paint_v2;master.tryserver.blink:linux_trusty_blink_rel
Reviewed-on: https://chromium-review.googlesource.com/1124701Reviewed-by: Xianzhu Wang <wangxianzhu@chromium.org>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#572302}

third_party/blink/renderer/core/frame/local_frame_view.cc

@@ -2530,9 +2530,8 @@ bool LocalFrameView::UpdateLifecyclePhasesInternal(
       // See crbug.com/667547
       bool print_mode_enabled = frame_->GetDocument()->Printing() &&
                                 !RuntimeEnabledFeatures::PrintBrowserEnabled();
-      bool repainted_paint_controller = false;
       if (!print_mode_enabled)
-        repainted_paint_controller = PaintTree();
+        PaintTree();
 
       if (!RuntimeEnabledFeatures::SlimmingPaintV2Enabled()) {
         if (layout_view->Compositor()->InCompositingMode()) {
@@ -2553,8 +2552,7 @@ bool LocalFrameView::UpdateLifecyclePhasesInternal(
 
           // Notify the controller that the artifact has been pushed and some
           // lifecycle state can be freed (such as raster invalidations).
-          if (repainted_paint_controller)
-            paint_controller_->FinishCycle();
+          paint_controller_->FinishCycle();
           // PaintController for BlinkGenPropertyTrees is transient.
           if (RuntimeEnabledFeatures::BlinkGenPropertyTreesEnabled())
             paint_controller_ = nullptr;
@@ -2725,7 +2723,7 @@ static void CollectDrawableLayersForLayerListRecursively(
   CollectDrawableLayersForLayerListRecursively(context, layer->MaskLayer());
 }
 
-bool LocalFrameView::PaintTree() {
+void LocalFrameView::PaintTree() {
   TRACE_EVENT0("blink,benchmark", "LocalFrameView::paintTree");
   SCOPED_UMA_AND_UKM_TIMER("Blink.Paint.UpdateTime", UkmMetricNames::kPaint);
 
@@ -2739,7 +2737,6 @@ bool LocalFrameView::PaintTree() {
     frame_view.Lifecycle().AdvanceTo(DocumentLifecycle::kInPaint);
   });
 
-  bool repainted_paint_controller = false;
   if (RuntimeEnabledFeatures::SlimmingPaintV2Enabled()) {
     if (!paint_controller_)
       paint_controller_ = PaintController::Create();
@@ -2762,7 +2759,6 @@ bool LocalFrameView::PaintTree() {
       PaintInternal(graphics_context, kGlobalPaintNormalPhase,
                     CullRect(LayoutRect::InfiniteIntRect()));
       paint_controller_->CommitNewDisplayItems();
-      repainted_paint_controller = true;
     }
   } else {
     // A null graphics layer can occur for painting of SVG images that are not
@@ -2813,7 +2809,6 @@ bool LocalFrameView::PaintTree() {
     CollectDrawableLayersForLayerListRecursively(
         context, layout_view->Compositor()->PaintRootGraphicsLayer());
     paint_controller_->CommitNewDisplayItems();
-    repainted_paint_controller = true;
   }
 
   ForAllNonThrottledLocalFrameViews([](LocalFrameView& frame_view) {
@@ -2821,8 +2816,6 @@ bool LocalFrameView::PaintTree() {
     if (auto* layout_view = frame_view.GetLayoutView())
       layout_view->Layer()->ClearNeedsRepaintRecursively();
   });
-
-  return repainted_paint_controller;
 }
 
 void LocalFrameView::PushPaintArtifactToCompositor(

third_party/blink/renderer/core/frame/local_frame_view.h

@@ -664,10 +664,7 @@ class CORE_EXPORT LocalFrameView final
   void NotifyFrameRectsChangedIfNeededRecursive();
   void UpdateStyleAndLayoutIfNeededRecursive();
   void PrePaint();
-  // Returns true if paint_controller_ is repainted. The return value is not
-  // used for non-BlinkGenPropertyTrees/SPv2 where paint_controller_ doesn't
-  // exist.
-  bool PaintTree();
+  void PaintTree();
 
   void UpdateStyleAndLayoutIfNeededRecursiveInternal();
 

third_party/blink/renderer/platform/graphics/graphics_layer.cc

@@ -286,7 +286,7 @@ void GraphicsLayer::PaintRecursively() {
   PaintRecursivelyInternal(repainted_layers);
 
   // Notify the controllers that the artifact has been pushed and some
-  // lifecycle state can be updated.
+  // lifecycle state can be freed (such as raster invalidations).
   for (auto* layer : repainted_layers) {
 #if DCHECK_IS_ON()
     if (VLOG_IS_ON(2))
@@ -335,13 +335,10 @@ bool GraphicsLayer::Paint(const IntRect* interest_rect,
     return false;
 #endif
 
-  bool repainted = false;
-  if (PaintWithoutCommit(interest_rect, disabled_mode)) {
-    repainted = true;
+  if (PaintWithoutCommit(interest_rect, disabled_mode))
     GetPaintController().CommitNewDisplayItems();
-  } else if (!needs_check_raster_invalidation_) {
+  else if (!needs_check_raster_invalidation_)
     return false;
-  }
 
 #if DCHECK_IS_ON()
   if (VLOG_IS_ON(2)) {
@@ -372,7 +369,7 @@ bool GraphicsLayer::Paint(const IntRect* interest_rect,
   }
 
   needs_check_raster_invalidation_ = false;
-  return repainted;
+  return true;
 }
 
 bool GraphicsLayer::PaintWithoutCommit(